steve trachtenberg is 75. >> i'm still cooking with gas, but i'm not the man i was at 65 or 55. >> solman: even so, trachtenberg thinks traditional retirement at age 65 is too young. >> people live longer now and are healthier longer now. but i think having an age at which the institution and the individual could together decide whether the person ought to retire would be a useful thing. >> solman: trachtenberg says 70 would be a good age to do that. so why does he continue to work at 75? >> well, if we had the conversation, i'd push back. i'd say, no, im still working! >> everybody's situation is different. >> solman: george mason psychology professor lou buffardi is retiring this spring at age 70. but he doesn't think everyone should. >> there are many folks my age and older who are remaining at the university and are some of our very best people. >> solman: sure, says claire potter, but there's a catch. >> i think one of the things you get if you have an aging faculty is, there's a kind of break on innovation that is unnecessary. younger people who are going into academia are more exci